<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style type="text/css">
        .box1{
            width: 100px;
            height: 100px;
            border:  solid green;
            background-color: green;
            display: flex;
        }
        .box2{
            width: 50%;
            height: 50%;
            background-color: red;
        }
    </style>
</head>
<body>
    <div class="box1">

        <div class="box2"></div>
        <div class="box2"></div>


    </div>
</body>
</html>